840 Area Code — San Bernardino, CA
Area code 840 serves San Bernardino and 2 other cities in California. Local time follows America/Los_Angeles. It overlays with 909, so 10-digit dialling is required.
- State
- California
- Primary city
- San Bernardino
- Timezone
- America/Los_Angeles
- In service since
- 2018
- Type
- Overlay
- Overlay codes
- 909
Overlay of 909
Cities Served by 840
The 840 area code covers 3 cities and communities in California.
- San Bernardino
- Riverside
- Ontario
About Area Code 840
Area code 840 is a North American Numbering Plan (NANP) area code that has been in service since 2018. It is administered by NANPA on behalf of the FCC and serves the California region anchored on San Bernardino.
840 is an overlay code, which means it shares its geographic boundaries with one or more existing area codes (909). Overlays are created when a region exhausts the supply of phone numbers in its original area code. Within an overlay region, residents must dial all 10 digits even for local calls, because the same 7-digit number can exist under multiple area codes.
Mobile numbers in 840 are portable: a person who moved away from San Bernardino may still carry a 840 mobile number on their device. If you receive an unexpected call from a 840 number, run it through the reverse lookup tool above for the most accurate, free identification.
If you live or do business in California, you may also interact with neighbouring or overlay codes (909). See the related codes section below to explore the rest of California.
Other California Area Codes
Continue exploring the California numbering plan.
840 Area Code FAQ
Where is area code 840?
Area code 840 is located in California, primarily serving San Bernardino and surrounding cities including Riverside, Ontario. The region operates on PT (America/Los_Angeles) time.
What state is 840 area code?
840 is a California area code. It was put into service in 2018 as an overlay and shares its geographic footprint with overlay code 909.
Is 840 a scam area code?
840 is a legitimate North American area code allocated by NANPA to California. Like any geographic area code, scammers sometimes spoof 840 numbers — judge each call by content (urgent demands, unfamiliar transfers) rather than the area code alone. Run the specific number through our reverse lookup if you're unsure.
What time zone does 840 use?
Area code 840 operates on PT (America/Los_Angeles). Numbers in this area code follow standard California time-zone rules including any daylight-saving transitions for that region.
Can I look up a specific 840 phone number?
Yes. Use the reverse lookup widget above to enter a full 840 number. NumLocation returns the line type (mobile, landline, VoIP), carrier, rate-center city, and any public listings tied to the number — free.
What's the difference between 840 and 909?
840 and 909 cover the same California geographic area as overlay codes. Calls between them are local, but you must dial all 10 digits. New phone numbers in this region are assigned from either pool depending on what's available with the carrier at signup.